JPS61270205A - Production of carbon foam - Google Patents

Abstract

PURPOSE:To obtain inexpensively carbon foam, by packing caking coal or pitch having a volatile content in a limited range to a mold, calcining the caking coal or pitch at a temperature not to make it into a liquid state so that bulk is made, and calcining it further at a high temperature. CONSTITUTION:One or more raw materials selected from caking coal and pitch having 15-30wt% volatile content of content are packed into a mold. The caking coal or the pitch is calcined at 380-500 deg.C, made into bulk, the bulk is calcined again at >=750 deg.C high temperature, sufficiently contracted, the atomic arrangement of carbon constituting the bulk is made into a firm three- dimensional crosslinking, and strength is improved, to give the aimed carbon foam. Consequently the high-quality carbon foam can be produced by a simple production process from the caking coal or the pitch which is inexpensively obtainable in a large amount. The obtained carbon foam is used as a high- temperature heat-insulating material or a corrosion-resistant filter medium for liquid.

Description

【発明の詳細な説明】 産業上の利用分野 この発明は、高温での断熱材、耐食性流体の濾過材、軽
量構造材等に用いられるカーボンフオームに係り、特に
粘結炭やピッチ類を原料とするカーボンフオームの製造
方法に関する。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to carbon foam used in high-temperature insulation materials, corrosion-resistant fluid filtration materials, lightweight structural materials, etc. The present invention relates to a method for producing carbon foam.

従来技術とその問題点 従来のカーボンフオームの製造方法としては、■フェノ
ールフオームあるいはウレタンフオームを焼成する方法
（米国特許第３１２１０５０．第３３４２５５５゜第３
３０２９９９等）、■炭素微小中空球全バインダーで固
めた後焼成する方法（特開昭４９−１０６４９１等）、
■炭素質物質を気孔形成材と混合処理した後焼成する方
法（特開昭４８−１８１８５．特開昭５７−５１１０９
等）、■合成樹脂等の有機材料を発泡させ不融化処理後
に焼成する方法（特開昭５７−３４００４等）、■ピッ
チまたは石炭の溶剤抽出成分ｔ−２段階で焼成する方法
（特開昭５６−３２３１４等）が知られている。Prior art and its problems Conventional methods for producing carbon foam include: ■ A method of firing phenol foam or urethane foam (U.S. Pat. No. 3,121,050, No. 3,342,555, No. 3)
302999, etc.), ■ A method of hardening carbon micro hollow spheres with a binder and then firing them (Japanese Patent Application Laid-open No. 49-106491, etc.),
■ A method of mixing carbonaceous material with a pore-forming material and then firing it (JP-A-48-18185, JP-A-57-51109)
etc.), ■ A method of foaming an organic material such as a synthetic resin and firing it after infusibility treatment (Japanese Patent Laid-Open No. 57-34004, etc.); ■ A method of firing at the t-2 stage of solvent extracted components of pitch or coal (Japanese Patent Laid-Open No. 57-34004, etc.) 56-32314 etc.) are known.

しかし、いずれの方法も発泡性原料が特殊で高価である
こと、製造工程が複雑であること等が原因してコストが
高くつく欠点がある。例えば、石炭やピッチ類を原料と
する前記■の方法の場合、出発原料である石炭やピッチ
類はそれ自体安価であるも、石炭やピッチ類から得られ
る溶剤抽出成分を発泡性原料として用いる九め、工程的
に複雑な溶剤抽出プロセスを必要とし、得られる抽出成
分は高価につくのみならず、成分範囲に制約があるため
その単独発泡体で気孔率や気孔分布を制御することは困
難である。そのため、特開昭５６−３２３１４にみられ
るように、第１段で得られる発泡体に溶剤抽出成分中の
液体分を含浸させて気孔構造を制御する第２段の処理全
必要とする工程上の複雑さが要求され、最終製品として
のカーボンフオームが高価とならざるを得なかった。However, both methods have drawbacks such as high costs due to special and expensive foamable raw materials and complicated manufacturing processes. For example, in the case of method (2) above, which uses coal or pitches as raw materials, although the starting materials, such as coal or pitches, are themselves inexpensive, it is also Therefore, a complicated solvent extraction process is required, and the extracted components obtained are not only expensive, but also have restrictions on the range of components, making it difficult to control the porosity and pore distribution of the single foam. be. Therefore, as seen in JP-A-56-32314, the entire process of the second stage, in which the foam obtained in the first stage is impregnated with the liquid content of the solvent-extracted components to control the pore structure, is necessary. This required complexity, and the carbon foam as a final product had to be expensive.

このように、カーボンフオームは高温での断熱材、耐食
性流体の濾過材、軽量構造材等の用途に広く用いること
のできる素材であっても、従来の製造技術では、発泡性
原料の特殊性、製造工程の複雑化のため、コストが高く
つき、その用途も限られていた。In this way, carbon foam is a material that can be widely used for high-temperature insulation materials, corrosion-resistant fluid filtration materials, lightweight structural materials, etc., but with conventional manufacturing technology, Due to the complexity of the manufacturing process, costs were high and its applications were limited.

発　　明　　の　　目　　的 この発明は、従来の前記実情にかんがみなされたもので
あり、カーボンフオームを安価に製造し得る方法全提案
することを目的とするものである。OBJECT OF THE INVENTION The present invention has been made in view of the above-mentioned conventional situation, and its purpose is to propose a complete method for manufacturing carbon foam at low cost.

発　　明　　の　　構　成 この発明に係るカーボンフオームの製造方法は、粘結炭
および揮発分１５〜３０％のピッチ類の１種または２種
以上からなる原料を型枠に充填し、３８０〜５００℃の
温度で焼成し念後、さらに７５０℃以上の高温にて再焼
成することを特徴とする感のである。Structure of the Invention The method for producing carbon foam according to the present invention includes filling a mold with a raw material consisting of one or more types of caking coal and pitch with a volatile content of 15 to 30%, and heating the material at 380 to 500°C. It is characterized by being fired at a temperature of 750°C or higher, and then re-fired at a high temperature of 750°C or higher.

石炭やピッチ類を原料としてカーボンフオームを製造す
る方法は、前記■の方法が知られているが、従来の方法
は石炭やピッチ類から得られる溶剤抽出成分を用いるた
め、前記したように発泡性原料が高価につく上、工程上
の複雑さが要求され、カーボンフオームが高価とならざ
るを得なかつ念。Method (2) above is known as a method for producing carbon foam using coal and pitches as raw materials, but the conventional method uses solvent-extracted components obtained from coal and pitches, so as mentioned above, foamability The raw materials are expensive and the process is complex, making carbon foam unavoidably expensive.

この発明は、石炭の中で一般に粘結炭と称される発泡性
を有する石炭やピッチ類の単独もしくはそれらの混合物
からカーボンフオームを得る方法であり、原料に制約が
なく、簡単な手段でカーボンフオームの製造を可能とし
たものである。This invention is a method for obtaining carbon foam from coal, which has a foaming property generally called coking coal, alone or from a mixture thereof, and there are no restrictions on raw materials, and carbon foam can be obtained by simple means. This made it possible to manufacture foam.

この発明において、カーボンフオームの製造原料として
粘結炭およびピッチ類を用いるのは、以下に示す理由に
よる。In this invention, the reason why caking coal and pitches are used as raw materials for producing carbon foam is as follows.

粘結炭は加熱過程で軟化溶融しながら熱分解ガスの発生
により発泡膨張する性質を有する九め、発泡性原料とし
て考えることができる。粘結炭は石炭化度の差、石炭組
織成分の差、酸化の程度によって発泡の程度が大きく異
なるため、カーボンフオーム製造原料としての選択範囲
は非常に広い。Caking coal can be thought of as a foaming raw material that has the property of softening and melting during heating and foaming and expanding due to the generation of pyrolysis gas. The degree of foaming of caking coal varies greatly depending on the degree of coalification, the composition of the coal, and the degree of oxidation, so the range of selection as a raw material for producing carbon foam is very wide.

従って、粘結炭の種類を適当に選ぶことにより、任意の
気孔構造をもったカーボンフす一ムの製造が原理的には
可能である。一方、ピッチ類についても粘結炭と同様に
加熱によって軟化溶融しながら熱分解ガスの発生により
発泡膨張する性質を有し、また石炭系と石油系の原料差
、蒸留条件や熱分解条件の差等により、その発泡の程度
が異なることから、カーボンフオーム製造原料としての
選択範囲は粘結炭と同様に広い。Therefore, by appropriately selecting the type of coking coal, it is possible in principle to produce a carbon frame with any pore structure. On the other hand, similar to coking coal, pitches have the property of softening and melting when heated, and then foaming and expanding due to the generation of pyrolysis gas, as well as differences in raw materials between coal-based and petroleum-based materials, as well as differences in distillation conditions and pyrolysis conditions. Since the degree of foaming differs depending on the type of carbon, the range of selection as a raw material for producing carbon foam is as wide as that of caking coal.

さらに、粘結炭やピッチ類は周知のとおり大量かつ安価
に得ることができる。Furthermore, as is well known, caking coal and pitches can be obtained in large quantities and at low cost.

従って、粘結炭やピッチ類の単独もしくはそれらの混合
物を発泡性原料として用いることは、コヌト面および工
程上極めて有利である。Therefore, the use of caking coal or pitch alone or a mixture thereof as a foamable raw material is extremely advantageous from the viewpoint of conut and the process.

この発明では、前記発泡性原料を型枠内に充填し、３８
０〜５００℃の温度で焼成して塊成化するが、ここで重
要なことは、■焼成温度を原料の塊成化に必要な温度に
とどめること、■型枠内の原料、持ニζピッチ類を加熱
過程で液体状態としないことである。そのなめ、この発
明では、原料の塊成化に必要な温度として３８０〜５０
０℃に限定し、また液体状態を回避すべくピッチ類を限
定した。In this invention, the foamable raw material is filled into a mold, and
The material is agglomerated by firing at a temperature of 0 to 500°C, but the important things here are: ■ Keeping the firing temperature at the temperature necessary for agglomerating the raw material; ■ Keeping the raw material in the formwork, Pitches should not be turned into a liquid state during the heating process. Therefore, in this invention, the temperature required for agglomerating the raw material is 380 to 50.
The temperature was limited to 0°C, and pitches were limited to avoid a liquid state.

すなわち、原料の種類によっては塊成化に必要な発泡膨
張の温度が若干異なるものの、少なくとも３８０℃以上
の温度であれば塊成化が可能であり、また塊成化後の急
激な収縮により型枠て拘束されて焼成物に亀裂が生じな
い５００℃以下の適当な温度範囲を選ぶ必要がある。か
かる知見より、この発明では焼成温度を３８０〜５００
℃に限定した。ま九、液体状態となるのを回避する理由
は、型枠内の充填原料が発泡以前にいったん液体状態全
経由する場合、カーボンフオームの気孔構造の調整が困
難となるばかりでなく、型枠内で・局部的に品質偏差を
生ずることになり製品価＠Ｉを落すためである。このよ
うな液体状態を回避するにはｗ、＠の選　　□択が重要
で、粘結炭の場合は特に問題はないが、一般に大部分の
ピッチ類は液体状態になる。しかし、揮発分が３０％以
下のピッチ類は液体状態を経由することなく、また揮発
分が１５％以上のビフチ類は発泡性も失なわれないこと
から、揮発分１５〜３０％の範囲のピッチ類を選べば液
体状ａｔ−経由することなく十分な焼成物を得ることが
できる。従って、この発明では原料として用いるピッチ
類を揮発分１５〜３０％の範囲のものに限定した。In other words, although the foaming expansion temperature required for agglomeration differs slightly depending on the type of raw material, agglomeration is possible at a temperature of at least 380°C or higher, and the rapid contraction after agglomeration causes the mold to collapse. It is necessary to select an appropriate temperature range of 500° C. or lower, where cracks do not occur in the fired product due to frame restraint. Based on this knowledge, in this invention, the firing temperature is set to 380 to 500.
℃. 9. The reason for avoiding the liquid state is that if the filling material in the formwork passes through the liquid state before foaming, it will not only be difficult to adjust the pore structure of the carbon foam, but also This is because it causes local quality deviations and lowers the product price @I. In order to avoid such a liquid state, the selection of w and @ is important.There is no particular problem in the case of coking coal, but generally most pitches are in a liquid state. However, pitches with a volatile content of 30% or less do not pass through the liquid state, and bifuchis with a volatile content of 15% or more do not lose their foaming properties. If pitches are selected, sufficient baked products can be obtained without passing through the liquid state. Therefore, in this invention, pitches used as raw materials are limited to those having a volatile content of 15 to 30%.

なお、原料の粒度および充填密度については、製品とな
るカーボンフオームの品質目標（気孔率、気孔分布等）
に応じて調製する。The particle size and packing density of the raw materials are determined based on the quality goals (porosity, pore distribution, etc.) of the carbon foam that becomes the product.
Prepare accordingly.

このようにして型枠内で焼成した塊成物（以下「グリー
ンフオーム」と称する）は、さらに７５０℃以上の高温
にて再焼成する。その理由は、３８０〜５００℃の温度
で焼成して得られたグリーンフオームは、強度も低く収
縮も不十分であり、カーボンフオームとして実用できな
いためである。ここで、再焼成温度ラフ５０℃以上に限
定したのは、グリーンフオームの大きな収縮が７５０℃
以下の温度で起こり、その間にグリーンフオームを構成
する炭素の原子配列が強固な３次元架橋となり、強度も
大幅に向上する九めである。なお、再焼成温度の上限に
ついては、高ければ高い程フオームの炭素結合が＠固と
なる念め好ましいが、熱経済性と製品用途によって決め
るべきものであるため特に限定されるものではない。The agglomerate thus fired within the mold (hereinafter referred to as "green form") is further fired at a high temperature of 750° C. or higher. The reason is that the green foam obtained by firing at a temperature of 380 to 500° C. has low strength and insufficient shrinkage, and cannot be put to practical use as a carbon foam. Here, the re-firing temperature was limited to a rough temperature of 50°C or higher because the large shrinkage of the green form was 750°C.
This occurs at the following temperatures, during which the carbon atomic arrangement that makes up the green form becomes a strong three-dimensional crosslink, and its strength is greatly improved. It should be noted that the upper limit of the re-firing temperature is preferably higher because the carbon bonds in the form become more solid, but it is not particularly limited as it should be determined based on thermo-economic efficiency and product usage.

グリーンフオームの再焼成は、型枠に入れたまま行なう
か、または型枠から取出して行なう。ただ、再焼成時に
はグリーンフオームが極めて大きな収縮を起こすため、
型枠に入れたまま再焼成する場合は、収縮時に型枠の形
状が障害となってフオームに亀裂が生じるおそれがある
。ま之、再焼成温度が高いと耐熱性型枠が変形するおそ
れがある。従って、型枠からグリーンフオームを取出し
て焼成するか、そのまま焼成するかは、型枠の形状およ
び再焼成温度等の処理条件を考慮して決定すればよい。The green foam can be refired while still in the mold or removed from the mold. However, because the green form undergoes extremely large shrinkage during re-firing,
If the foam is refired while still in the form, the shape of the form may become an obstacle during shrinkage and cracks may occur in the form. However, if the re-firing temperature is high, there is a risk that the heat-resistant formwork will be deformed. Therefore, whether to take out the green form from the mold and fire it or to fire it as is can be determined by considering the shape of the mold and processing conditions such as re-firing temperature.

第１図はこの発明方法で使用する型枠の一例を示すもの
で、（１）は両端開口の円盤状型枠、（２）は型枠上蓋
、（３）は型枠下蓋、（４）は型枠締付はポルト、（５
）は発泡性原料である。型枠の構成部材はすべて耐熱性
であることはいうまでもない。型枠の形状としては円盤
状以外に、円筒形や箱形状のものもある。盤状のような
型枠の場合はグリーンフオームの収縮時に前記のような
障害は起こらないが、円筒状や箱形状の場合は収縮時の
障害となるため、このような場合は型枠からグリーンフ
オームを取出して再焼成することにより製品となるカー
ボンフオームの品質欠陥を防ぐことができる。FIG. 1 shows an example of a formwork used in the method of the present invention, in which (1) is a disc-shaped formwork with openings at both ends, (2) is an upper lid of the formwork, (3) is a lower lid of the formwork, and (4) is a disc-shaped formwork with openings at both ends. ) is Porto for formwork tightening, (5
) is a foamable raw material. It goes without saying that all the constituent members of the formwork are heat resistant. The shape of the formwork is not only disc-shaped, but also cylindrical and box-shaped. If the formwork is disk-shaped, the above-mentioned problem will not occur when the green form contracts, but if it is cylindrical or box-shaped, it will be a problem when the green form contracts. By taking out the foam and re-firing it, it is possible to prevent quality defects in the carbon foam that becomes the product.

実施例１ 第１表に示す３種の粘結炭について、それぞれ６０メツ
シユ（０，２５ｆｉ）以下で１００メツシユ（０，１４
９ｍ１１１）以上に粉砕調製後、第１図に示す内径ＩＱ
Ｏｗ。Example 1 Regarding the three types of coking coal shown in Table 1, 100 mesh (0,14
After grinding to a size of 9m111) or more, the inner diameter IQ shown in Figure 1
Ow.

厚さ７鱈の鋼製型枠に充填密度０．６ｙ／ｄで充填し、
１５ＫＶＡの電気炉で常温より２℃／分の加熱速度で昇
温し、それぞれ３７０℃、４３０℃、４７０℃、５１０
℃まで焼成後１０分間保持して得たグリーンフオームの
性状金第２表に示す。A steel formwork with a thickness of 7 yen was filled with a filling density of 0.6 y/d,
The temperature was raised from room temperature at a heating rate of 2°C/min in a 15KVA electric furnace to 370°C, 430°C, 470°C, and 510°C, respectively.
The properties of the green foam obtained by holding it for 10 minutes after firing at ℃ are shown in Table 2.

第　　　２　　　表 第２表の結果より、粘結炭Ａ、　Ｂ、　Ｃとも焼成温度
が３７０℃では塊成化が不十分で円板の形状を成さない
か、形状は保持しても脆くて全く強度のないものであり
、３８０℃以上の焼成温度が必要と判断される。また、
５１０℃の焼成では体積収縮が大きく、グリーンフオー
ムに亀裂を生じるため、５００℃以上の焼成温度は塊成
化温度としては不適当と判断される。一方、グリーンフ
オームの性状として重要な見掛密度については、揮発分
の高い粘結炭Ａが小さい見掛密度となってシリ、適当に
炭種を選ぶことで気孔構造を調整できることが確認され
九。なお、粘結炭Ｃは粘結炭Ｂのビトリニットを主成分
とする活性成分を比重分離により濃縮したもので、石炭
化度は変わらないものの、不活性成分が除去されている
ため灰分が少なく、不純物の少ないグリーンフオームが
得られている。Table 2 From the results in Table 2, it can be seen that when the calcination temperature was 370°C, coking coals A, B, and C either did not agglomerate sufficiently and did not form a disk shape, or were brittle even if they retained their shape. It has no strength at all, and it is judged that a firing temperature of 380°C or higher is required. Also,
Firing at 510°C causes large volume shrinkage and cracks in the green form, so a firing temperature of 500°C or higher is judged to be inappropriate as an agglomeration temperature. On the other hand, regarding the apparent density, which is an important property of green foam, it was confirmed that caking coal A with high volatile content has a small apparent density and that the pore structure can be adjusted by selecting an appropriate coal type. . Coking coal C is a product obtained by concentrating the active components of coking coal B, mainly consisting of vitrinite, through specific gravity separation, and although the degree of coalification remains the same, the ash content is low because the inert components have been removed. A green form with few impurities is obtained.

これらの結果より、粘結脚管型枠内で焼成し、体積収縮
を抑え、かつ安定した塊成化を達成するには３８０〜５
００℃の温度範囲が適当であるとぎえる。From these results, in order to suppress volumetric shrinkage and achieve stable agglomeration by firing in a sticky leg tube form,
A temperature range of 00°C is considered suitable.

次に、粘結炭Ａ、　Ｂ、　Ｃの中で温度４３０℃と４７
０℃の各焼成物を４５０℃に保持された１５ＫＶＡの電
気炉に装入し、窒素雰囲気下で２℃／分の加熱速度で昇
温し、それぞれ６５０℃、７５０℃、８５０℃。Next, temperatures of 430°C and 47°C were set in coking coals A, B, and C.
Each fired product at 0°C was placed in a 15KVA electric furnace maintained at 450°C, and heated at a heating rate of 2°C/min in a nitrogen atmosphere to 650°C, 750°C, and 850°C, respectively.

１０００℃まで再焼成後、１０分間保持してｗ４九カー
ボンフす−ムの性状を第３表に示す。Table 3 shows the properties of the W49 carbon film after re-firing to 1000°C and holding for 10 minutes.

第３表より、いずれのグリーンフオーム％１ｌａｔ。From Table 3, any green form% 1lat.

温度の上昇にともない収縮し、強度の向上が認められる
ものの、６５０℃焼成では収縮が不十分で強度は低い。Although it shrinks as the temperature rises and the strength improves, the shrinkage is insufficient and the strength is low when fired at 650°C.

しかし、７５０℃以上の焼成温度では大きな収縮は完了
し、強度も６５０℃焼成のものに比べて大きく向上して
いる。従って、グリーンフオームの高温焼成温度として
は少なくとも７５０℃以上が必要と言える。また、カー
ポンプオームの性状としては見掛密度が低く、気孔率が
高いにもかかわらず高い強度を示し、良好なフオームで
あることがわかる。また、特に注目すべきことは、グリ
ーンフオームを製造する時の焼成温度の差、すなわち４
３０℃焼成と４７０℃焼成のカーボンフオームに与える
影響は顕著ではないことである。すなわち、グリーンブ
す−ムの段階で十分な粒子結合が達成され塊成化されて
いれば、カーボンフオームの品質は十分確保されること
が理解される。ま危、例えば粘結炭ＡとＢとから得られ
る１０００℃焼成のカーボンフオームの比較では、粘結
炭人由来のカーポンプす−ムが粘結炭Ｂ由来のカーボン
フオームより曲げ強度は低いものの見掛密度が低く、気
孔率が高いことである。これは、第１表に見られるとお
り、原料である粘結炭ＡとＢの揮発分の差にもとづくカ
ーボン歩留りの差に起因して１八ると推察できる。すな
わち、粘結炭の種類を適当に選択することにより、得ら
れるカーボンフオームの気孔構造を任意に調整できるこ
とを意味する。さらに注目すべき点は、粘結炭Ｃ由来の
カーポンプす−ムは不純物としての灰分量が粘結炭Ａ。However, at a firing temperature of 750°C or higher, the large shrinkage is completed and the strength is greatly improved compared to that fired at 650°C. Therefore, it can be said that the high-temperature firing temperature of the green foam is required to be at least 750°C or higher. In addition, it can be seen that the properties of Carpon Ohm are low in apparent density and high strength despite high porosity, indicating that it is a good foam. Also, what is particularly noteworthy is the difference in firing temperature when producing green foam, that is, 4
The effects of firing at 30°C and 470°C on the carbon form are not significant. That is, it is understood that if sufficient particle bonding is achieved and agglomeration is achieved at the green form stage, the quality of the carbon foam is sufficiently ensured. For example, when comparing carbon forms fired at 1000°C obtained from coking coals A and B, the carbon foam derived from coking coal was found to have lower bending strength than the carbon form derived from coking coal B. It has a low wall density and a high porosity. As shown in Table 1, it can be inferred that this is 18 due to the difference in carbon yield based on the difference in volatile content between coking coals A and B, which are raw materials. This means that by appropriately selecting the type of coking coal, the pore structure of the resulting carbon foam can be adjusted as desired. A further noteworthy point is that the carpump system derived from coking coal C has an ash content of coking coal A as an impurity.

Ｂ由来のものよりはるかに少ないということである。こ
れは、前記し念ように粘結炭Ｃが粘結炭Ｂを比重分離に
よりビトリニット成分を主成分とする活性成分を濃縮し
て得られたものであることから、同じ粘結炭といえども
事前処理によりカーボンフオームの品質をより高めるこ
とが可能であることを示している。This means that it is much less than that derived from B. This is because, as mentioned above, coking coal C is obtained by concentrating the active ingredients mainly composed of vitrinite components from coking coal B through specific gravity separation, so even though it is the same coking coal, This shows that it is possible to further improve the quality of carbon foam through pre-treatment.

（以下余白） 第　　　　３　　　表 実施例２ コールタ−々ピッチを減圧下で加熱処理条件を変えて得
られた第４表に示す４種のピッチについて、実施例１と
同様の操作を行なって得たグリーンフす−ムの性状を第
５表に示す。(Leaving space below) Table 3 Example 2 Four types of pitches shown in Table 4 obtained by changing heat treatment conditions under reduced pressure were obtained by performing the same operations as in Example 1. Table 5 shows the properties of the green frame.

第５表の結果より、ピッチＤ、　Ｅは焼成温度３７０℃
で塊成化し、円板形状を保持しているものの、ピッチＦ
、　Ｇは塊成化が不十分であつ九。特にピッチＧはいず
れの焼成温度でも塊成化せずグリーンフオームを作製で
きなかった。これは、ピッチＧは揮発分が低すぎ、発泡
膨張性が悪く、粒子の融着が不十分になつ九ためと推察
される。一方、ピッチＤはいずれの温度でも塊成化し、
グリーン７す−ムを得ることはできるものの、フす−ム
の気孔構造が不均質で欠陥も多く、強度は低い。これは
、ピッチＤは揮発分が高いため軟化温度が低くなりすぎ
、発泡膨張する以前に溶融し、液体状態となる丸め型枠
内の上部に空間を生じ、発泡膨張時には上部と下部で気
孔構造に差が生じるためと推察される。しかしながら、
３７０℃、４３０℃。From the results in Table 5, the firing temperature for pitches D and E is 370°C.
Although it agglomerates and retains the disc shape, the pitch F
, G is insufficiently agglomerated. In particular, pitch G did not agglomerate at any firing temperature and no green form could be produced. This is presumably because Pitch G has too low a volatile content, has poor foaming expansion properties, and results in insufficient particle fusion. On the other hand, pitch D agglomerates at any temperature,
Although it is possible to obtain a green 7 frame, the pore structure of the frame is non-uniform and there are many defects, and the strength is low. This is because Pitch D has a high volatile content, so its softening temperature is too low, and it melts before foaming and expanding, creating a space in the upper part of the rounding form where it becomes liquid. This is presumed to be due to the difference in however,
370℃, 430℃.

４７０℃焼成のピッチＥおよび４３０℃、４７０℃焼成
のピッチＦは、均質で強度の高いフオームが得られた。For pitch E fired at 470°C and pitch F fired at 430°C and 470°C, homogeneous and high strength foams were obtained.

しかし、両ピッチとも５１０℃焼成で大きな収縮を示し
、焼成温度は高すぎると判断された。However, both pitches showed large shrinkage when fired at 510°C, and the firing temperature was judged to be too high.

これらの・結果より、ピッチ類の場合も型枠内で体積収
縮を抑え、かつ安定した塊成化を達成するには、３８０
〜５００℃の温度範囲が適当で、また揮発分は１５〜３
０％の範囲のものが良好なグリーンフオームを得るに適
することがわかる。なお、ピッチ類から得られるグリー
ンフオームは第４表から明らかなように、原料ピッチ中
の灰分量が少ないので、当然のことながらグリーンフオ
ームの灰分量も少なく高品質である。From these results, in the case of pitches, in order to suppress volumetric shrinkage within the formwork and achieve stable agglomeration, 380
A temperature range of ~500℃ is suitable, and the volatile content is 15~3
It can be seen that a range of 0% is suitable for obtaining a good green form. As is clear from Table 4, the green foam obtained from pitches has a low ash content in the raw pitch, so naturally the green foam has a low ash content and is of high quality.

第　　　４　　　表 第　　　５　　　表 次に、ピッチＥ、Ｆの温度４３０℃と４７０℃の各焼成
物を実施例１と同様の操作を行なって得たカーボンフオ
ームの性状を第６表に示す。Table 4 Table 5 Next, Table 6 shows the properties of carbon foam obtained by performing the same operation as in Example 1 on the fired products of pitches E and F at temperatures of 430°C and 470°C.

第６表より、いずれのグリーンフオームも焼成温度の上
昇にともない収縮し、強度の向上が認められるものの、
６５０℃焼成では収縮が不十分で強度は低い。しかし、
７５０℃以上の温度での再焼成では、大きな収縮は完了
し、強度も大きく向上している。従って、実施例１の粘
結炭の場合と同様、グリーンフオームの高温焼成温度と
しては少なくとも７５０℃以上が必要と言える。また、
カーボンフオームの性状としても高い強度を示し、良好
なフオームであることがわかる。ま九、ピッチ由来のカ
ーボンフオームの場合は粘結炭由来のカーボンフオーム
に比べて不純物としての灰分量が低く良好であることが
わかる。From Table 6, it can be seen that all green forms contract as the firing temperature increases, and although an improvement in strength is observed,
When fired at 650°C, shrinkage is insufficient and strength is low. but,
Re-firing at a temperature of 750° C. or higher completes the large shrinkage and greatly improves the strength. Therefore, as in the case of the caking coal in Example 1, it can be said that the high-temperature firing temperature of the green foam is required to be at least 750°C or higher. Also,
It can be seen that the carbon foam exhibits high strength and is a good foam. Also, it can be seen that the carbon foam derived from pitch has a lower ash content as an impurity and is better than the carbon foam derived from coking coal.

（以下余白） 第６表 発　　明　　の　　効　　果 上記の実施例からも明らかなごとく、この発明によれば
、安価で大量に入手できる粘結炭やピッチ類を原料とし
、製造工程も簡単にして品質良好なカーボンフオームを
製造することが可能であり、さらに原料の選択や粘結炭
の比重分離等の若干の事前処理によりカーボンフオーム
の品質全任意に調整することができ、カーボンフオーム
の汎用化に大きく貢献し得る。(Leaving space below) Table 6 Effects of the Invention As is clear from the above embodiments, according to the present invention, caking coal and pitch, which are inexpensive and available in large quantities, are used as raw materials, and the manufacturing process is simplified. It is possible to produce carbon foam with good quality, and the quality of carbon foam can be adjusted to any desired level by selecting raw materials and performing some pre-processing such as separating the specific gravity of coking coal, making carbon foam more versatile. can greatly contribute to

【図面の簡単な説明】[Brief explanation of the drawing]

第１図はこの発明方法を実施するための型枠の一例を示
す縦断面図である。 １・・・円盤状型枠、２・・・型枠上蓋、３・・・型枠
下蓋、４・・・締付はボルト、５・・・発泡性原料。 出願人　　住友金属工業株式会社 いFIG. 1 is a longitudinal sectional view showing an example of a formwork for carrying out the method of this invention. 1... Disk-shaped formwork, 2... Formwork upper lid, 3... Formwork lower cover, 4... Bolts for tightening, 5... Foamable raw material. Applicant: Sumitomo Metal Industries, Ltd.

Claims (1)

【特許請求の範囲】[Claims] 粘結炭および揮発分１５〜３０％のピッチ類の１種また
は２種以上からなる原料を型枠に充填し、３８０〜５０
０℃の温度で焼成し塊成化した後、さらに７５０℃以上
の高温にて再焼成することを特徴とするカーボンフォー
ムの製造方法。A mold is filled with a raw material consisting of one or more types of caking coal and pitches with a volatile content of 15 to 30%, and
A method for producing carbon foam, which comprises firing at a temperature of 0°C to form agglomerates, and then re-firing at a high temperature of 750°C or higher.